The population of sable Martez zibellina consisting of two subspecies (M. z. kamtschadalica and M. z. jacutensis) on the territory of the Magadan oblast was analyzed for the variation of the 1300-bp mtDNA gene region encoding cytochrome b. Three haplotypes were revealed among the animals studied (n = 52). Six out of nine restriction endonucleases that had recognizable sites within the studied region of mtDNA genome had polymorphic sites. An index of gene diversity h was 0.27. The high level of polymorphism is a result of the fact that the population studied comprised two clearly differentiated subspecies. The ratio of dominating haplotypes corresponds to the percentage of females introduced from Kamchatka and Khabarovsk Krai, which suggests that in the period which has elapsed both maternal lineages remained fairly unchanged.